The repairing of dams is carried out in environments that involve many constraints: infrastructure having an important slope; work surfaces varying between 0-90.degree.; security of the workers; important weight of the equipment, and vibrations produced by certain types of equipment (e.g. drill); delays for the work; complex installations; required precision in the work achievement; non conventional scaffolding; limited workspace; difficult and limited access; cluttering of the work areas.
The execution of the work requires complex logistics which must adapt to the environmental conditions and ensure the security of the workers. At this time, the work is carried out on precarious installations that do not respect certain or all of the aforesaid constraints.
The conventional method for the execution of the work on dam runners requires the full-time mobilization of a crane, the continuous moving of scaffolding, the operation of tools on various work surfaces, a constricting security program, many persons to meet the needs of the workers, exhausting work for the drillers, long delays in the fulfilment of the work, etc. For example, the project manager establishes the work methods and the appropriate directives, and plane the intervention of subcontractors, the site operations, the various work stages, the work schedule and the budgets. He proceeds with the purchase and rental of the material, equipment and other required elements, and then to the design of the scaffolding with the assistance of a structure engineer to meet the requirements of the contractor, the committee for social security and health, and the owner. The contractor then proceeds with the production of the scaffolding according to the plants Procedures are developed for the set-up of the equipment and the tools, and their removal when the work is finished. To install the scaffolding and continuously move it, for example, to drill holes at various locations, a crane must be installed permanently during the entire time of the work execution. At each move, the scaffolding must be anchored on its base, which takes time and requires considerable labour force. The staircase of the scaffolding must be lengthened on the entire length of the runner during displacement of the scaffolding, which represents highly important equipment costs. The drilling of holes is executed by hand, which constitutes a very exhausting and dangerous work for the workers.